16-2071891-C-T

Variant summary

Our verdict is Uncertain significance. The variant received 4 ACMG points: 4P and 0B. PM2PP3_Moderate

The NM_000548.5(TSC2):​c.2054C>T​(p.Pro685Leu) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000025 in 1,597,218 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. P685R) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 33)
Exomes 𝑓: 0.0000021 ( 0 hom. )

Consequence

TSC2
NM_000548.5 missense

Scores

9
9
1

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:2

Conservation

PhyloP100: 7.30

Publications

0 publications found
Variant links:
Genes affected
TSC2 (HGNC:12363): (TSC complex subunit 2) This gene is a tumor suppressor gene that encodes the growth inhibitory protein tuberin. Tuberin interacts with hamartin to form the TSC protein complex which functions in the control of cell growth. This TSC protein complex negatively regulates mammalian target of rapamycin complex 1 (mTORC1) signaling which is a major regulator of anabolic cell growth. Mutations in this gene have been associated with tuberous sclerosis and lymphangioleiomyomatosis. [provided by RefSeq, May 2022]
TSC2 Gene-Disease associations (from GenCC):
  • tuberous sclerosis
    Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
  • tuberous sclerosis 2
    Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: PanelApp Australia, Laboratory for Molecular Medicine, Labcorp Genetics (formerly Invitae), G2P, Genomics England PanelApp, Ambry Genetics
  • lymphangioleiomyomatosis
    Inheritance: AD Classification: STRONG Submitted by: Genomics England PanelApp
  • tuberous sclerosis complex
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 4 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PP3
MetaRNN computational evidence supports a deleterious effect, 0.896

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TSC2NM_000548.5 linkc.2054C>T p.Pro685Leu missense_variant Exon 19 of 42 ENST00000219476.9 NP_000539.2 P49815-1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
TSC2ENST00000219476.9 linkc.2054C>T p.Pro685Leu missense_variant Exon 19 of 42 5 NM_000548.5 ENSP00000219476.3 P49815-1

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152262
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.000288
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00
Gnomad OTH
AF:
0.00
GnomAD4 exome
AF:
0.00000208
AC:
3
AN:
1444956
Hom.:
0
Cov.:
33
AF XY:
0.00000279
AC XY:
2
AN XY:
717426
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33122
American (AMR)
AF:
0.00
AC:
0
AN:
42988
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25734
East Asian (EAS)
AF:
0.00
AC:
0
AN:
38914
South Asian (SAS)
AF:
0.00
AC:
0
AN:
83748
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
50642
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5672
European-Non Finnish (NFE)
AF:
0.00000272
AC:
3
AN:
1104480
Other (OTH)
AF:
0.00
AC:
0
AN:
59656
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.475
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.00000657
AC:
1
AN:
152262
Hom.:
0
Cov.:
33
AF XY:
0.0000134
AC XY:
1
AN XY:
74390
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41474
American (AMR)
AF:
0.00
AC:
0
AN:
15292
Ashkenazi Jewish (ASJ)
AF:
0.000288
AC:
1
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5196
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4838
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10628
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68040
Other (OTH)
AF:
0.00
AC:
0
AN:
2094
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.425
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.00000378

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:2
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Tuberous sclerosis 2 Uncertain:1
Aug 08, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces proline, which is neutral and non-polar, with leucine, which is neutral and non-polar, at codon 685 of the TSC2 protein (p.Pro685Leu). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with TSC2-related conditions. ClinVar contains an entry for this variant (Variation ID: 1016081). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is not expected to disrupt TSC2 protein function with a negative predictive value of 95%. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Hereditary cancer-predisposing syndrome Uncertain:1
Nov 14, 2023
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.P685L variant (also known as c.2054C>T), located in coding exon 18 of the TSC2 gene, results from a C to T substitution at nucleotide position 2054. The proline at codon 685 is replaced by leucine, an amino acid with similar properties. This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Uncertain
0.53
BayesDel_addAF
Pathogenic
0.42
D
BayesDel_noAF
Pathogenic
0.36
CADD
Uncertain
25
DANN
Pathogenic
1.0
DEOGEN2
Pathogenic
0.91
D;.;.;.;.;.;.;.;.;.;.;.;D;.;D
Eigen
Uncertain
0.67
Eigen_PC
Uncertain
0.63
FATHMM_MKL
Pathogenic
0.98
D
LIST_S2
Pathogenic
0.99
D;D;D;D;D;D;D;D;D;D;D;D;D;D;D
M_CAP
Pathogenic
0.39
D
MetaRNN
Pathogenic
0.90
D;D;D;D;D;D;D;D;D;D;D;D;D;D;D
MetaSVM
Uncertain
0.50
D
MutationAssessor
Uncertain
2.7
M;.;.;.;M;M;.;.;.;M;.;M;.;.;.
PhyloP100
7.3
PrimateAI
Uncertain
0.78
T
PROVEAN
Uncertain
-4.3
D;.;.;D;.;D;.;.;D;D;.;.;.;.;D
REVEL
Pathogenic
0.84
Sift
Uncertain
0.0050
D;.;.;D;.;D;.;.;D;D;.;.;.;.;D
Sift4G
Uncertain
0.0030
D;.;.;D;.;D;.;.;D;D;.;.;.;.;D
Polyphen
1.0
D;.;.;.;D;D;.;.;D;D;.;.;.;.;.
Vest4
0.95
MutPred
0.71
Loss of disorder (P = 0.0525);Loss of disorder (P = 0.0525);Loss of disorder (P = 0.0525);.;Loss of disorder (P = 0.0525);Loss of disorder (P = 0.0525);Loss of disorder (P = 0.0525);Loss of disorder (P = 0.0525);.;Loss of disorder (P = 0.0525);Loss of disorder (P = 0.0525);Loss of disorder (P = 0.0525);Loss of disorder (P = 0.0525);Loss of disorder (P = 0.0525);.;
MVP
0.92
ClinPred
0.99
D
GERP RS
5.5
Varity_R
0.36
gMVP
0.71
Mutation Taster
=20/80
disease causing

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.0
Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

Other links and lift over

dbSNP: rs959165669; hg19: chr16-2121892; API